Fluid, particularly blood, is drawn from patients on a routine basis in many hospitals and laboratories. One of the most common ways to draw blood is venipuncture, which is a method that involves inserting a needle through the skin and into an underlying vein. In some instances blood can be drawn as frequently as every six hours. Further, patients can be subjected to multiple attempts each time a needle is inserted into the skin, and the more frequent the withdrawals become, the more difficult it can become to find a location for the next withdrawal. Each attempt can be painful and a nuisance. Other options for the withdrawal of blood and other fluids, however, are limited, and can often be even more painful than venipuncture. Some of these options include the use of Peripherally Inserted Central Catheters (PICC lines), central lines, repeated peripheral venipuncture, and groin sticks.
Current guidelines allow blood to be drawn off a peripheral intravenous catheter at the time of insertion. Studies show that blood sampled from a peripheral intravenous catheter yields results similar to those obtained by venipuncture. Clots, however, tend to form at the tip of an intravenous catheter, so it is generally not desirable to draw blood from peripheral intravenous catheters as they are currently designed. The clots can be both dangerous and painful. Further, as blood is drawn from peripheral intravenous catheters, the tip of the intravenous catheters can become damaged. A damaged intravenous catheter tip can lead to compromised blood samples and undesirable harm or damage to the instrumentation and the patient.
Accordingly, it is desirable to have devices and methods that allow for less painful and more dependable blood sampling and fluid removal from a patient. It is also desirable to have devices and methods that allows for multiple samples to be taken over a period of time from the same puncture site.